450 How Do Brushless Motors Really Work?

murankar

murankar

Staff member
Yes it is, but its a function of the esc not the motor. The important thing with the motor is the timing. If you get that wrong you could under power your motor or over power the motor (which means burn it up). Hobby wing V4 escs work, pros use them on all kinds of motors with great success. Justin and Nick did a digging in episode for RCHN on escs and how they work. There was also and normal episode where they geeked out over it in a speed application. I don't remember which episode it was.
 
Rob Lancaster

Rob Lancaster

Well-Known Member
Ok, I think I got it now. I was getting confused because of the motor specs. I thought for a second that the motors drive speed (8kHz), should be set by the esc like the timing is. I just learned this is not the case.

While were at it; what is the RCHN??
Are their videos on this topic?

"Thank you for the support"
And your well come...…..
 
murankar

murankar

Staff member
Rc Heli Nation 2.0 was a podcast. Adult language is pg-17 type.

Anyhow I think what the 8khz is in the esc is the rate at which the mosfets cycle through the phases. Not completely sure on that.
 
Rob Lancaster

Rob Lancaster

Well-Known Member
No my motor has a 8kHz spec and you mentioned earlier that the Hobbywing V4 ESCs are preset to 36kHz...
I figure if the two numbers were reversed, the ESC couldn't keep up with the motor. Right??
The way it is now, the ESC has plenty of head room and can easily switch fast enough for the motor; right?

You said RCHN was a pod cast... Is it any good?
Fun, fun, fun...……
Rob...
 
Tony

Tony

Staff member
He thinks it's good. I am not in that group. They asked me to join their cast a long time ago and I refused.
 
Tony

Tony

Staff member
The motor KHz rating is only for the ESC, it has nothing to do with the motor per say. If you go too low on the khz then the motor will be noisy. Higher is not as noisy. Again, it's all in the ESC and the motor description stating 8 is just a generic setting for the ESC.
 
Rob Lancaster

Rob Lancaster

Well-Known Member
Tony said:
The motor KHz rating is only for the ESC, it has nothing to do with the motor per say. If you go too low on the khz then the motor will be noisy. Higher is not as noisy. Again, it's all in the ESC and the motor description stating 8 is just a generic setting for the ESC.
Click to expand...

Oh ok, it's just an electrical interference thing then...
Thanks crew!
Rster...
 
Tony

Tony

Staff member
It was nothing against them or what they do, they just didn't match what I was trying to get across with my site and channel. They were very outgoing and spoke their mind, and back then, I was trying to make this the friendliest place on the net for RC Information and Help. There is no denying, their knowledge was way above what I could provide, I jsut didn't want to be acquainted with them at the time.

I have since changed the way I run this site, meaning that I'm not that overly strict admin anymore. If they asked me tomorrow to join, I might just do it.

And yup, it's just the timing at which the ESC turns on and off the FET's. A motor is a large electromagnet, and thus just absorbs the pulses much like a capacitor. If you want to know what I mean by that, look at the capacitors function in a buck converter.
 
Rob Lancaster

Rob Lancaster

Well-Known Member
Oh so they weren't like the blow hard I knew once. Cool......lol!! :chairshot:

What's a Buck Converter? Even my brother has never heard of one of those...
 
Tony

Tony

Staff member
A buck converter is an AC to DC converter. Basically, it takes in a source, and it pulses on and off a certain amount of times to achieve a desired voltate. So lets say you have a 10 volt source, The FET will pulse on, and that is 10 volts, but them it turns off for a given amount of time. lets say it's 50/50. So 1ms on, and one ms off (ms is millisecond). That would equate to 5 volts. And because of the design, it would be DC (Direct Current). This is the same way a UBEC works on a helicopter. The capacitor is there to smooth out those pulses and give you a number that is equal to the amount of the time the FET was on.

There is a lot more than this to the explanation but my brain can't come up with the correct verbiage to explain it correctly.
 
Rob Lancaster

Rob Lancaster

Well-Known Member
Your fired!!!
Need a cool island for a vacation spot? Ha!!
We got Hughes 500's galore here!
My brother knows a good pilot. Think about it, he he heee......
Rster...
 
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murankar

murankar

Staff member
Generally buc stands for boost up converter. In the signal world we use them to increase the faint signal from a satellite. It receives the weak signal, boosts it up to 5v before sending it to the modem. If you know the army stt you'll know what I am saying. Just look it up.

In simple terms it takes a given supply voltage and changes it to a different desired voltage for output.
 
Rob Lancaster

Rob Lancaster

Well-Known Member
Wow the Wikipedia article is way hard core. This is going to take some time.
Hey Tony, I received my two Scorpion 1.5mm hex drivers today. Now these are nice! As my other hex drivers go south, I'll be replacing them with Scorpion drivers.
Thanks again all.
Rster...
 
Tony

Tony

Staff member
There are far easier articles on buck converters, but you have shown that you like details, and wiki gives you all the details lol.

and yes, those tools are amazing! Great investment in the hobby!
 
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